Revert content type of timeline RSS feed that I changed for debugging purposes in [1597].
Revert content type of timeline RSS feed that I changed for debugging purposes in [1597].

git-svn-id: f68c6b3b1dcd5d00a2560c384475aaef3bc99487@1601 af82e41b-90c4-0310-8c96-b1721e28e2e2

moreati/trac-gitsvn,dokipen/trac,exocad/exotrac,moreati/trac-gitsvn,dokipen/trac,exocad/exotrac,exocad/exotrac,dokipen/trac,exocad/exotrac,dafrito/trac-mirror,moreati/trac-gitsvn,dafrito/trac-mirror,dafrito/trac-mirror,dafrito/trac-mirror,moreati/trac-gitsvn